With the advent of cheap, bright light emitting diodes (LEDs), LED light arrays may be deployed as overhead lights in buildings, such as stores. LED light arrays have the capability to provide adequate area lighting, while being intensity modulated to communicate information, such as shopping information and the like, in a manner that is virtually imperceptible to humans. Conventional smartphones with built-in cameras provide Internet browsing and offer shopper friendly applications, such as global positioning system (GPS) store locator services. However, such applications fall short when it comes to guiding shoppers inside large superstores, for example, because GPS coverage may be lost indoors. While smartphones can capture pictures and videos, the smartphones are limited in their ability to process modulated light from overhead LED light arrays in a manner that supports intelligent applications, such as indoor position determination and guidance that may augment GPS positioning.
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